Non‐linear charge conduction and emission behaviour of OELD fabricated with Alq3 and TPD‐doped soluble polyimide

Synthesis and Characteristics of Poly[N,N‘-diphenyl-N,N‘-bis(4-aminobiphenyl)-(1,1‘-biphenyl)-4,4‘-diamine pyromellitimide] as a Hole Injecting and Transporting Layer for Hybrid Organic Light-Emitting Device

“…The J-V plot shows the typical regimes such as an ohmic (m ) 0.3), a space charge limited (m ) 1), a trap charge limited (m ) 1.7), and a trap-free space charge limited (m ) 1) in the power-law model (J ≈ V m+1 ). 51 In addition to the typical regimes, another regime (m ) 0.3) similar to an ohmic was observed at high electric field. From the relatively low m value compared to the other reports, 51 it is considered that a small trap state exists in the present HOD even though the device passes hole car-riers only.…”

“…51 In addition to the typical regimes, another regime (m ) 0.3) similar to an ohmic was observed at high electric field. From the relatively low m value compared to the other reports, 51 it is considered that a small trap state exists in the present HOD even though the device passes hole car-riers only. The ionization potential of the PI thin film on the ITO substrate was obtained as 5.12 eV by the ultraviolet photoelectron spectroscopy (UPS) method described in the previous work.…”

“…The current density−voltage ( J − V ) characteristic of the HOD fabricated with the PI thin film is shown in Figure . The J − V plot shows the typical regimes such as an ohmic ( m = 0.3), a space charge limited ( m = 1), a trap charge limited ( m = 1.7), and a trap-free space charge limited ( m = 1) in the power-law model ( J ≈ V m +1 ) . In addition to the typical regimes, another regime ( m = 0.3) similar to an ohmic was observed at high electric field.…”

Synthesis and Characteristics of Poly[N,N‘-diphenyl-N,N‘-bis(4-aminobiphenyl)-(1,1‘-biphenyl)-4,4‘-diamine pyromellitimide] as a Hole Injecting and Transporting Layer for Hybrid Organic Light-Emitting Device

“…The J-V plot shows the typical regimes such as an ohmic (m ) 0.3), a space charge limited (m ) 1), a trap charge limited (m ) 1.7), and a trap-free space charge limited (m ) 1) in the power-law model (J ≈ V m+1 ). 51 In addition to the typical regimes, another regime (m ) 0.3) similar to an ohmic was observed at high electric field. From the relatively low m value compared to the other reports, 51 it is considered that a small trap state exists in the present HOD even though the device passes hole car-riers only.…”

“…51 In addition to the typical regimes, another regime (m ) 0.3) similar to an ohmic was observed at high electric field. From the relatively low m value compared to the other reports, 51 it is considered that a small trap state exists in the present HOD even though the device passes hole car-riers only. The ionization potential of the PI thin film on the ITO substrate was obtained as 5.12 eV by the ultraviolet photoelectron spectroscopy (UPS) method described in the previous work.…”

“…The current density−voltage ( J − V ) characteristic of the HOD fabricated with the PI thin film is shown in Figure . The J − V plot shows the typical regimes such as an ohmic ( m = 0.3), a space charge limited ( m = 1), a trap charge limited ( m = 1.7), and a trap-free space charge limited ( m = 1) in the power-law model ( J ≈ V m +1 ) . In addition to the typical regimes, another regime ( m = 0.3) similar to an ohmic was observed at high electric field.…”

Wide band gap triarylamine derivative doped with organosulfonic acid and its application for organic light-emitting devices

“…[3,4] Hence, we guess that this different EL spectral shape might be caused by the emission zone shift depending on the TPD-CSA content. Because the Alq 3 layer emits only green light even though the TPD-doped PEI layers with various TPD contents were used as a HTL, [35] the red part contribution in the EL spectra is considered to originate from the TPD-CSA:PEI layer when it comes to the result that the broad range PL (green to orange red) was measured for the TPD-CSA solution (see Figure 3(b)). As shown in Figure 5(b), the TPD-CSA:PEI films exhibited an orange red PL upon excitation at 460 nm (note that very small optical absorptions were measured for all films at the wavelengths between 400 and 500 nm as observed similarly for the TPD-CSA solutions in Figure 3(b)) (see also Figure S3 for another optical absorption measurement for clarity).…”

An Electronically Active Molecularly Doped Polyimide Hole Injection Layer for an Efficient Hybrid Organic Light-Emitting Device

“…Unfortunately, the transition temperature of the AMDPI films could not be measured here because more than 3 mg of powder is typically required for the DSC measurement. However, from the glass transition temperature of the pristine NPB (∼95 °C) and the API powders, that of the AMDPI powder consisting of 50 wt % NPB molecules can be theoretically calculated as ∼148 °C on the basis of the well-known Fox equation …”

Synthesis and Characteristics of Poly[N,N‘-diphenyl-N,N‘-bis(4-aminobiphenyl)-(1,1‘-biphenyl)-4,4‘-diamine pyromellitimide] as a Hole Injecting and Transporting Layer for Hybrid Organic Light-Emitting Device

“…The J-V plot shows the typical regimes such as an ohmic (m ) 0.3), a space charge limited (m ) 1), a trap charge limited (m ) 1.7), and a trap-free space charge limited (m ) 1) in the power-law model (J ≈ V m+1 ). 51 In addition to the typical regimes, another regime (m ) 0.3) similar to an ohmic was observed at high electric field. From the relatively low m value compared to the other reports, 51 it is considered that a small trap state exists in the present HOD even though the device passes hole car-riers only.…”

“…51 In addition to the typical regimes, another regime (m ) 0.3) similar to an ohmic was observed at high electric field. From the relatively low m value compared to the other reports, 51 it is considered that a small trap state exists in the present HOD even though the device passes hole car-riers only. The ionization potential of the PI thin film on the ITO substrate was obtained as 5.12 eV by the ultraviolet photoelectron spectroscopy (UPS) method described in the previous work.…”

“…The current density−voltage ( J − V ) characteristic of the HOD fabricated with the PI thin film is shown in Figure . The J − V plot shows the typical regimes such as an ohmic ( m = 0.3), a space charge limited ( m = 1), a trap charge limited ( m = 1.7), and a trap-free space charge limited ( m = 1) in the power-law model ( J ≈ V m +1 ) . In addition to the typical regimes, another regime ( m = 0.3) similar to an ohmic was observed at high electric field.…”

Wide band gap triarylamine derivative doped with organosulfonic acid and its application for organic light-emitting devices

“…[3,4] Hence, we guess that this different EL spectral shape might be caused by the emission zone shift depending on the TPD-CSA content. Because the Alq 3 layer emits only green light even though the TPD-doped PEI layers with various TPD contents were used as a HTL, [35] the red part contribution in the EL spectra is considered to originate from the TPD-CSA:PEI layer when it comes to the result that the broad range PL (green to orange red) was measured for the TPD-CSA solution (see Figure 3(b)). As shown in Figure 5(b), the TPD-CSA:PEI films exhibited an orange red PL upon excitation at 460 nm (note that very small optical absorptions were measured for all films at the wavelengths between 400 and 500 nm as observed similarly for the TPD-CSA solutions in Figure 3(b)) (see also Figure S3 for another optical absorption measurement for clarity).…”

An Electronically Active Molecularly Doped Polyimide Hole Injection Layer for an Efficient Hybrid Organic Light-Emitting Device

“…Unfortunately, the transition temperature of the AMDPI films could not be measured here because more than 3 mg of powder is typically required for the DSC measurement. However, from the glass transition temperature of the pristine NPB (∼95 °C) and the API powders, that of the AMDPI powder consisting of 50 wt % NPB molecules can be theoretically calculated as ∼148 °C on the basis of the well-known Fox equation …”

Synthesis and Characteristics of Poly[N,N‘-diphenyl-N,N‘-bis(4-aminobiphenyl)-(1,1‘-biphenyl)-4,4‘-diamine pyromellitimide] as a Hole Injecting and Transporting Layer for Hybrid Organic Light-Emitting Device

“…The J-V plot shows the typical regimes such as an ohmic (m ) 0.3), a space charge limited (m ) 1), a trap charge limited (m ) 1.7), and a trap-free space charge limited (m ) 1) in the power-law model (J ≈ V m+1 ). 51 In addition to the typical regimes, another regime (m ) 0.3) similar to an ohmic was observed at high electric field. From the relatively low m value compared to the other reports, 51 it is considered that a small trap state exists in the present HOD even though the device passes hole car-riers only.…”

“…51 In addition to the typical regimes, another regime (m ) 0.3) similar to an ohmic was observed at high electric field. From the relatively low m value compared to the other reports, 51 it is considered that a small trap state exists in the present HOD even though the device passes hole car-riers only. The ionization potential of the PI thin film on the ITO substrate was obtained as 5.12 eV by the ultraviolet photoelectron spectroscopy (UPS) method described in the previous work.…”

“…The current density−voltage ( J − V ) characteristic of the HOD fabricated with the PI thin film is shown in Figure . The J − V plot shows the typical regimes such as an ohmic ( m = 0.3), a space charge limited ( m = 1), a trap charge limited ( m = 1.7), and a trap-free space charge limited ( m = 1) in the power-law model ( J ≈ V m +1 ) . In addition to the typical regimes, another regime ( m = 0.3) similar to an ohmic was observed at high electric field.…”

Wide band gap triarylamine derivative doped with organosulfonic acid and its application for organic light-emitting devices

“…[3,4] Hence, we guess that this different EL spectral shape might be caused by the emission zone shift depending on the TPD-CSA content. Because the Alq 3 layer emits only green light even though the TPD-doped PEI layers with various TPD contents were used as a HTL, [35] the red part contribution in the EL spectra is considered to originate from the TPD-CSA:PEI layer when it comes to the result that the broad range PL (green to orange red) was measured for the TPD-CSA solution (see Figure 3(b)). As shown in Figure 5(b), the TPD-CSA:PEI films exhibited an orange red PL upon excitation at 460 nm (note that very small optical absorptions were measured for all films at the wavelengths between 400 and 500 nm as observed similarly for the TPD-CSA solutions in Figure 3(b)) (see also Figure S3 for another optical absorption measurement for clarity).…”

An Electronically Active Molecularly Doped Polyimide Hole Injection Layer for an Efficient Hybrid Organic Light-Emitting Device

“…Unfortunately, the transition temperature of the AMDPI films could not be measured here because more than 3 mg of powder is typically required for the DSC measurement. However, from the glass transition temperature of the pristine NPB (∼95 °C) and the API powders, that of the AMDPI powder consisting of 50 wt % NPB molecules can be theoretically calculated as ∼148 °C on the basis of the well-known Fox equation …”